1. Field of the Invention
The present invention generally relates to operations panels and image forming apparatuses, and more particularly an operations panel having a push-button mechanism having a key top and an image forming apparatus having the operations panel.
2. Description of the Related Art
Plural optional keys corresponding to functions or operations of an image forming apparatus having plural functions such as a copier or printer are arranged on a surface of an interface of the image forming apparatus. A key top of the optional keys has a structure where, for example, a pressing part pressed from outside and a flexible claw for engaging a housing of the apparatus or the like are formed in a body by plastic injection molding. The key top is fitted in the housing by the flexible claw in a state where only designated sliding is permitted. See, for example, Japanese Laid-Open Patent Application Publication No. 7-85751.
Since a hinge structure cannot be applied to the key top and the housing, after the key top is fitted in the housing from the outside, due to unevenness of clearance between a key boss provided at the key top in order to operate a switch and the switch, the key top may be vibrated so that strange noise may be generated. In addition, due to fall of the key top from the surface of the housing, operations feeling may be damaged.
Furthermore, in the interface of the copier or the like, plural neighboring key tops having different functions but common configurations of operations surfaces are frequently arranged. In this case, since the distance between the switch and the key top is the same in each of the key tops, it is possible to commonly use the key top having the same configuration by printing an indication on the operations surface of the key top having the designated length different. However, depending on a design configuration of a cover of the operations panel or a housing of the copier or the like having the key top, it may be necessary to make the length of the key boss different, depending on the arrangement position of the key top. Therefore, the key tops having the same configurations may not be commonly used.